1/*
2 * Copyright (C) 2008 Apple Inc. All Rights Reserved.
3 * Copyright (C) 2011, 2012 Google Inc. All Rights Reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 */
27
28#include "config.h"
29
30#if ENABLE(WORKERS)
31
32#include "WorkerScriptController.h"
33
34#include "JSDOMBinding.h"
35#include "JSDedicatedWorkerContext.h"
36#include "ScriptSourceCode.h"
37#include "ScriptValue.h"
38#include "WebCoreJSClientData.h"
39#include "WorkerContext.h"
40#include "WorkerObjectProxy.h"
41#include "WorkerScriptDebugServer.h"
42#include "WorkerThread.h"
43#include <heap/StrongInlines.h>
44#include <interpreter/Interpreter.h>
45#include <runtime/Completion.h>
46#include <runtime/ExceptionHelpers.h>
47#include <runtime/Error.h>
48#include <runtime/JSLock.h>
49
50#if ENABLE(SHARED_WORKERS)
51#include "JSSharedWorkerContext.h"
52#endif
53
54using namespace JSC;
55
56namespace WebCore {
57
58WorkerScriptController::WorkerScriptController(WorkerContext* workerContext)
59    : m_vm(VM::create())
60    , m_workerContext(workerContext)
61    , m_workerContextWrapper(*m_vm)
62    , m_executionForbidden(false)
63{
64    initNormalWorldClientData(m_vm.get());
65}
66
67WorkerScriptController::~WorkerScriptController()
68{
69    JSLockHolder lock(vm());
70    m_workerContextWrapper.clear();
71    m_vm.clear();
72}
73
74void WorkerScriptController::initScript()
75{
76    ASSERT(!m_workerContextWrapper);
77
78    JSLockHolder lock(m_vm.get());
79
80    // Explicitly protect the global object's prototype so it isn't collected
81    // when we allocate the global object. (Once the global object is fully
82    // constructed, it can mark its own prototype.)
83    Structure* workerContextPrototypeStructure = JSWorkerContextPrototype::createStructure(*m_vm, 0, jsNull());
84    Strong<JSWorkerContextPrototype> workerContextPrototype(*m_vm, JSWorkerContextPrototype::create(*m_vm, 0, workerContextPrototypeStructure));
85
86    if (m_workerContext->isDedicatedWorkerContext()) {
87        Structure* dedicatedContextPrototypeStructure = JSDedicatedWorkerContextPrototype::createStructure(*m_vm, 0, workerContextPrototype.get());
88        Strong<JSDedicatedWorkerContextPrototype> dedicatedContextPrototype(*m_vm, JSDedicatedWorkerContextPrototype::create(*m_vm, 0, dedicatedContextPrototypeStructure));
89        Structure* structure = JSDedicatedWorkerContext::createStructure(*m_vm, 0, dedicatedContextPrototype.get());
90
91        m_workerContextWrapper.set(*m_vm, JSDedicatedWorkerContext::create(*m_vm, structure, static_cast<DedicatedWorkerContext*>(m_workerContext)));
92        workerContextPrototypeStructure->setGlobalObject(*m_vm, m_workerContextWrapper.get());
93        dedicatedContextPrototypeStructure->setGlobalObject(*m_vm, m_workerContextWrapper.get());
94        ASSERT(structure->globalObject() == m_workerContextWrapper);
95        ASSERT(m_workerContextWrapper->structure()->globalObject() == m_workerContextWrapper);
96        workerContextPrototype->structure()->setGlobalObject(*m_vm, m_workerContextWrapper.get());
97        dedicatedContextPrototype->structure()->setGlobalObject(*m_vm, m_workerContextWrapper.get());
98#if ENABLE(SHARED_WORKERS)
99    } else {
100        ASSERT(m_workerContext->isSharedWorkerContext());
101        Structure* sharedContextPrototypeStructure = JSSharedWorkerContextPrototype::createStructure(*m_vm, 0, workerContextPrototype.get());
102        Strong<JSSharedWorkerContextPrototype> sharedContextPrototype(*m_vm, JSSharedWorkerContextPrototype::create(*m_vm, 0, sharedContextPrototypeStructure));
103        Structure* structure = JSSharedWorkerContext::createStructure(*m_vm, 0, sharedContextPrototype.get());
104
105        m_workerContextWrapper.set(*m_vm, JSSharedWorkerContext::create(*m_vm, structure, static_cast<SharedWorkerContext*>(m_workerContext)));
106        workerContextPrototype->structure()->setGlobalObject(*m_vm, m_workerContextWrapper.get());
107        sharedContextPrototype->structure()->setGlobalObject(*m_vm, m_workerContextWrapper.get());
108#endif
109    }
110    ASSERT(m_workerContextWrapper->globalObject() == m_workerContextWrapper);
111    ASSERT(asObject(m_workerContextWrapper->prototype())->globalObject() == m_workerContextWrapper);
112}
113
114void WorkerScriptController::evaluate(const ScriptSourceCode& sourceCode)
115{
116    if (isExecutionForbidden())
117        return;
118
119    ScriptValue exception;
120    evaluate(sourceCode, &exception);
121    if (exception.jsValue()) {
122        JSLockHolder lock(vm());
123        reportException(m_workerContextWrapper->globalExec(), exception.jsValue());
124    }
125}
126
127void WorkerScriptController::evaluate(const ScriptSourceCode& sourceCode, ScriptValue* exception)
128{
129    if (isExecutionForbidden())
130        return;
131
132    initScriptIfNeeded();
133
134    ExecState* exec = m_workerContextWrapper->globalExec();
135    JSLockHolder lock(exec);
136
137    JSValue evaluationException;
138    JSC::evaluate(exec, sourceCode.jsSourceCode(), m_workerContextWrapper.get(), &evaluationException);
139
140    if ((evaluationException && isTerminatedExecutionException(evaluationException)) ||  m_workerContextWrapper->vm().watchdog.didFire()) {
141        forbidExecution();
142        return;
143    }
144
145    if (evaluationException) {
146        String errorMessage;
147        int lineNumber = 0;
148        String sourceURL = sourceCode.url().string();
149        if (m_workerContext->sanitizeScriptError(errorMessage, lineNumber, sourceURL, sourceCode.cachedScript()))
150            *exception = ScriptValue(*m_vm, throwError(exec, createError(exec, errorMessage.impl())));
151        else
152            *exception = ScriptValue(*m_vm, evaluationException);
153    }
154}
155
156void WorkerScriptController::setException(const ScriptValue& exception)
157{
158    throwError(m_workerContextWrapper->globalExec(), exception.jsValue());
159}
160
161void WorkerScriptController::scheduleExecutionTermination()
162{
163    // The mutex provides a memory barrier to ensure that once
164    // termination is scheduled, isExecutionTerminating will
165    // accurately reflect that state when called from another thread.
166    MutexLocker locker(m_scheduledTerminationMutex);
167    m_vm->watchdog.fire();
168}
169
170bool WorkerScriptController::isExecutionTerminating() const
171{
172    // See comments in scheduleExecutionTermination regarding mutex usage.
173    MutexLocker locker(m_scheduledTerminationMutex);
174    return m_vm->watchdog.didFire();
175}
176
177void WorkerScriptController::forbidExecution()
178{
179    ASSERT(m_workerContext->isContextThread());
180    m_executionForbidden = true;
181}
182
183bool WorkerScriptController::isExecutionForbidden() const
184{
185    ASSERT(m_workerContext->isContextThread());
186    return m_executionForbidden;
187}
188
189void WorkerScriptController::disableEval(const String& errorMessage)
190{
191    initScriptIfNeeded();
192    JSLockHolder lock(vm());
193
194    m_workerContextWrapper->setEvalEnabled(false, errorMessage);
195}
196
197void WorkerScriptController::attachDebugger(JSC::Debugger* debugger)
198{
199    initScriptIfNeeded();
200    debugger->attach(m_workerContextWrapper->globalObject());
201}
202
203void WorkerScriptController::detachDebugger(JSC::Debugger* debugger)
204{
205    debugger->detach(m_workerContextWrapper->globalObject());
206}
207
208} // namespace WebCore
209
210#endif // ENABLE(WORKERS)
211